Optimizing therapy outcomes for peritoneal dialysis

ABSTRACT

Peritoneal dialysis therapy outcomes have been calculated for a variety of dwell times of peritoneal dialysis fluids in the peritoneal cavities of dialysis patients using kinetic modeling. The length of dwell time should not be the same for every patient, but should vary according to the patient condition and needs. Some patients have a potential for expressing greater ultrafiltrate into the dialysis fluid, and these patients can benefit from a longer dwell time, whereas other patients with less potential will not benefit from a longer dwell time. An optimal or peak time is observed for each peritoneal dialysis therapy outcome, such as ultrafiltrate volume rate, urea clearance (Kt/V), and creatinine clearance, while minimizing hydrocarbon absorption. These values and input parameters can be used to tailor the peritoneal dialysis dwell time for each patient, estimating the peak dwell time that will yield the best therapy outcome for each patient.

PRIORITY CLAIM

This application claims priority as a non-provisional application to,and the benefit of, U.S. Provisional Patent Application for “OPTIMIZINGTHERAPY OUTCOMES FOR PERITONEAL DIALYSIS”, Ser. No. 61/050,114, filedMay 2, 2008.

BACKGROUND

The present disclosure relates generally to medical fluid deliverysystems and methods. More particularly, this disclosure includessystems, methods and apparatuses for selecting a dwell time forperitoneal dialysis based on an individual patient's response todialysis, and also based on one or more peritoneal dialysis inputparameters. The dwell time is selected to yield the best therapy outcomefor that patient based on the dialysis parameters.

Due to various causes, a person's renal system can fail. Renal failureproduces several physiological impairments and difficulties. The balanceof water, minerals and the excretion of daily metabolic load is nolonger possible and toxic end products of nitrogen metabolism (urea,creatinine, uric acid, and others) can accumulate in blood and tissue.Kidney failure and reduced kidney function have been treated withdialysis. Dialysis removes waste, toxins and excess water from the bodythat would otherwise have been removed by normal functioning kidneys.Dialysis treatment for replacement of kidney functions is critical tomany people because the treatment is life saving.

Hemodialysis and peritoneal dialysis are two types of dialysis therapiesused commonly to treat loss of kidney function. A hemodialysis (“HD”)treatment utilizes the patient's blood to remove waste, toxins andexcess water from the patient. The patient is connected to ahemodialysis machine and the patient's blood is pumped through themachine. Catheters are inserted into the patient's veins and arteries sothat blood can flow to and from the hemodialysis machine. The bloodpasses through a dialyzer of the machine, which removes waste, toxinsand excess water from the blood. The cleaned blood is returned to thepatient. A large amount of dialysate, for example about 120 liters, isconsumed to dialyze the blood during a single hemodialysis therapy.Hemodialysis treatment lasts several hours and is generally performed ina treatment center about three or four times per week.

Another form of kidney failure treatment involving blood ishemofiltration (“HF”), which is an alternative renal replacement therapythat relies on a convective transport of toxins from the patient'sblood. This therapy is accomplished by adding substitution orreplacement fluid to the extracorporeal circuit during treatment(typically ten to ninety liters of such fluid). That substitution fluidand the fluid accumulated by the patient in between treatments isultrafiltered over the course of the HF treatment, providing aconvective transport mechanism that is particularly beneficial inremoving middle and large molecules.

Hemodiafiltration (“HDF”) is another blood treatment modality thatcombines convective and diffusive clearances. HDF uses dialysate to flowthrough a dialyzer, similar to standard hemodialysis, providingdiffusive clearance. In addition, substitution solution is provideddirectly to the extracorporeal circuit, providing convective clearance.

Peritoneal dialysis uses a dialysis solution, also called dialysate,which is infused into a patient's peritoneal cavity via a catheter. Thedialysate contacts the peritoneal membrane of the peritoneal cavity.Waste, toxins and excess water pass from the patient's bloodstream,through the peritoneal membrane and into the dialysate due to diffusionand osmosis, i.e., an osmotic gradient occurs across the membrane. Thespent dialysate is drained from the patient, removing waste, toxins andexcess water from the patient. This cycle is repeated.

Peritoneal dialysis machines are used to accomplish this task. Suchmachines are described, for example, in the following U.S. patents, allof which are incorporated by reference in their entirety, as though eachpatent were set forth herein, page by page, in its entirety: U.S. Pat.Nos. 5,350,357; 5,324,422; 5,421,823; 5,431,626; 5,438,510; 5,474,683;5,628,908; 5,634,896; 5,938,634; 5,989,423; 7,153,286; and 7,208,092.

There are various types of peritoneal dialysis therapies, includingcontinuous ambulatory peritoneal dialysis (“CAPD”), automated peritonealdialysis (“APD”), tidal flow APD and continuous flow peritoneal dialysis(“CFPD”). CAPD is a manual dialysis treatment. The patient manuallyconnects an implanted catheter to a drain, allowing spent dialysatefluid to drain from the peritoneal cavity. The patient then connects thecatheter to a bag of fresh dialysate, infusing fresh dialysate throughthe catheter and into the patient. The patient disconnects the catheterfrom the fresh dialysate bag and allows the dialysate to dwell withinthe peritoneal cavity, wherein the transfer of waste, toxins and excesswater takes place. After a dwell period, the patient repeats the manualdialysis procedure, for example, four times per day, each treatmentlasting about an hour. Manual peritoneal dialysis requires a significantamount of time and effort from the patient, leaving ample room forimprovement. There is room for improvement in the selection of dwelltimes for each patient.

Automated peritoneal dialysis (“APD”) is similar to CAPD in that thedialysis treatment includes drain, fill, and dwell cycles. APD machines,however, perform the cycles automatically, typically while the patientsleeps. APD machines free patients from having to manually perform thetreatment cycles and from having to transport supplies during the day.APD machines connect fluidly to an implanted catheter, to a source orbag of fresh dialysate and to a fluid drain. APD machines pump freshdialysate from a dialysate source, through the catheter, into thepatient's peritoneal cavity, and allow the dialysate to dwell within thecavity, and allow the transfer of waste, toxins and excess water to takeplace. The source can be multiple sterile dialysate solution bags.

APD machines pump spent dialysate from the peritoneal cavity, though thecatheter, to the drain. As with the manual process, several drain, filland dwell cycles occur during APD. A “last fill” occurs at the end ofCAPD and APD, which remains in the peritoneal cavity of the patientuntil the next treatment.

Both CAPD and APD are batch type systems that send spent dialysis fluidto a drain. Tidal flow systems are modified batch systems. With tidalflow, instead of removing all of the fluid from the patient over alonger period of time, a portion of the fluid is removed and replacedafter smaller increments of time.

Continuous flow, or CFPD, systems clean or regenerate spent dialysateinstead of discarding it. These systems pump fluid into and out of thepatient, through a loop. Dialysate flows into the peritoneal cavitythrough one catheter lumen and out another catheter lumen. The fluidexiting the patient passes through a reconstitution device that removeswaste from the dialysate, e.g., via a urea removal column that employsurease to enzymatically convert urea into ammonia. The ammonia is thenremoved from the dialysate by adsorption prior to reintroduction of thedialysate into the peritoneal cavity. Additional sensors are employed tomonitor the removal of ammonia. CFPD systems are typically morecomplicated than batch systems.

In each of the kidney failure treatment systems discussed above, it isimportant to control ultrafiltration, which is the process by whichwater (with electrolytes) moves across a membrane, such as a dialyzer orperitoneal membrane. For example, ultrafiltration in peritoneal dialysisis a result of transmembrane and osmotic pressure differences betweenblood and dialysate across the patient's peritoneal membrane. It is alsoimportant to control the concentration of metabolic substances in thepatient's bloodstream, such as urea concentration, β₂-microglobulin,creatinine concentration, and so forth. Each of these, along with manyother variables, constitutes a peritoneal dialysis outcome.

Each patient is different, possessing for instance, a unique peritonealmembrane, its own separation characteristics, and its unique response toperitoneal dialysis. Each patient is also different with respect to bodysurface area (BSA) and total body water volume, which also have aneffect on transport characteristics. Each patient is different in termsof transport characteristics that relate to the ultrafiltration rate.Each patient is also different in terms of response to dialysis, thatis, the amount of water and waste removed in a given time period, usinga given fill volume, a particular dialysis fluid, and so forth. What isneeded is a way to better control the particular dialysis therapyoffered to each patient, so that the treatment will yield the besttherapy outcome for that patient, for one or more dialysis inputparameters

While APD frees the patient from having to manually performing thedrain, dwell, and fill steps, a need still exists for CAPD. Somepatients prefer the control that CAPD offers. Since the patient is awakeduring CAPD, the patient can adjust himself/herself during drain toproduce more complete drains. Further, many patients who perform APDalso perform a midday exchange using a CAPD technique.

Since CAPD does not typically use a machine, advantages of using amachine are not available to the CAPD patient, such as features intendedto optimize therapy for the patent. It is therefore desirable to providea “smart” system that is applicable to both APD and CAPD systems.

SUMMARY

One embodiment is a method for accomplishing peritoneal dialysis. Themethod includes steps of administering a peritoneal equilibration test(PET) to a patient, determining and recording a patient status as aresult of the PET test, and calculating a peritoneal dialysis dwell timebased on the patient status and at least one peritoneal dialysis therapyoutcome, wherein the dwell time optimizes the at least one peritonealdialysis therapy outcome for the patient.

Another embodiment is a method for accomplishing peritoneal dialysis.The method includes steps of determining peritoneal transport propertiesof a patient, determining a classification of the peritoneal transportproperties of the patient, and calculating a peritoneal dialysis dwelltime based on the classification, a plurality of peritoneal dialysisinput parameters, and at least one desired peritoneal dialysis therapyoutcome, wherein the dwell time is calculated to maximize the at leastone desired peritoneal dialysis therapy outcome.

Another embodiment is a system for calculating a peritoneal dialysisdwell time and conducting peritoneal dialysis. The system includes aprocessor for operating a peritoneal dialysis machine, a memory of theprocessor or a memory accessible to the processor, the memory storing alook-up table containing peritoneal dialysis input parameters,peritoneal dialysis therapy outcomes, and peritoneal dialysis dwelltimes corresponding to the input parameters and dwell times, and asoftware program stored in the memory of the processor or the memoryaccessible to the processor for receiving a selection or an input of atleast one desired therapy outcome of a patient and calculating a dwelltime for the patient for optimizing the at least one peritoneal dialysistherapy outcome for the patient.

Another embodiment is a computer program embodied on a computer readablemedium for calculating a peritoneal dialysis dwell time. The computerprogram includes a code segment for accessing data of a correspondencebetween a plurality of peritoneal dialysis input parameters, a pluralityof peritoneal dialysis therapy outcomes, and a plurality of peritonealdialysis dwell times. The computer program also includes a code segmentthat allows a user to input or to select at least one peritonealdialysis input parameter from the plurality of peritoneal dialysis inputparameters and at least one desired therapy outcome; a code segment thatreceives an indication of the at least one input parameter and at leastone desired therapy outcome selected by the user; a code segment thatcalculates a dwell time corresponding to the at least one desiredtherapy outcome selected by the user; and a code segment that inputs thedwell time to the dialysis machine.

Another embodiment is a peritoneal dialysis system. The peritonealdialysis system includes a dialysis cassette and a housing suitable forreceiving the cassette, the cassette including at least one pump forpumping dialysis fluid to and from a patient; a microcontroller suitablefor operating the peritoneal dialysis system; a memory of themicrocontroller or accessible to the microcontroller, the memoryincluding data of a plurality of dialysis input parameters, a pluralityof dialysis dwell times, and a plurality of therapy outcomescorresponding to the input parameters and dwell times, wherein a userinstructs the microcontroller to select or calculate a dwell time foroptimizing at least one dialysis outcome for a patient; and a patienttransfer device in communication with the microcontroller.

In yet another embodiment, a system including a smart transfer set isprovided. The system includes a docking unit having a docking port thatreceives and holds the fill or solution bag line, and in oneimplementation a connector located at an end of the fill line. Theconnector (or perhaps the fill line itself) bears an identifier that inone embodiment identifies the dialysate solution type, solution volumeand solution expiration date.

The docking unit is provided with a reader that reads the identifier.The docking port and the fill line connector are configured to mate,such that the reader can read the identifier. The identifier can be abarcode, in which case the reader is a barcode reader. The identifier isalternatively a radio frequency identifier (“RFID”) tag, the reader anRFID reader, in which case the orientation of the connector within thedocking port may not be as critical.

The docking unit in one embodiment also includes a computer memorydevice port, such as a universal serial bus (“USB”) port. The portallows the patient to insert a memory device, such as a USB flash driveinto the USB port, which allows the patient to download patient specificdata to a memory located within the docking unit. That memory can alsobe used to store information read from the identifier. The docking unitin one embodiment includes processing that processes the informationgleaned from the identifier and the patient memory device and developstherapy parameters that are sent from the docking unit to the transferset. The transfer set is configured to communicate the parameterinformation to the patient, who uses the information to control aperitoneal dialysis therapy, such as a continuous ambulatory peritonealdialysis (“CAPD”) therapy. To this end, the docking unit is providedwith a transmitter (or transceiver) that transmits the parameterinformation, e.g., wirelessly to a receiver (or transceiver) locatedwithin the transfer set.

The transfer set also includes memory and processing, which interfacebetween the receiver and at least one output device for communicatingwith the patient, such as a light, buzzer or video display. The at leastone output device communicates therapy parameter information to thepatient, such as when to begin filling from the dialysate supply, whento attempt to have the fill completed, and when to drain spentdialysate, e.g., based on a determined dwell time. While the majority ofthe processing is done in the docking unit in one embodiment, it is alsocontemplated to let the transfer set do the majority of the processing,in which case the docking unit serves mainly to transfer information tothe transfer set for processing.

The therapy parameter information can be used in a number of ways. Inone embodiment, the transfer set also includes an input device that thepatient can activate once the patient is done filling from the dialysatecontainer. Here, the docking unit can determine an optimum dwellduration and send it to the transfer set. Once the patient activates theinput device, the transfer set beings a running of the optimal dwellduration. The transfer set can include a digital time remaining readoutor display that counts down to zero, for example. The transfer setadditionally or alternatively includes an alarm or buzzer thatcommunicates when the dwell duration has lapsed, signaling a patientdrain.

In another embodiment, the docking unit sends a fill duration and adwell duration to the smart transfer set. The fill duration isdetermined principally from the dialysate volume gleaned from theidentifier. The dwell duration is determined from the volume, thesolution type (e.g., glucose level) and patient parameters, such as PETparameters. The fill duration begins to run, giving the patient anadequate time to fill from the dialysate container. When the patientfill times out, the dwell duration begins to run. The transfer setcommunicates the running of the dwell duration according to any of theways discussed above. This embodiment does not require an input deviceor patient activation.

A third embodiment includes a fill duration and a dwell duration, likethe last embodiment. The docking unit also includes a sensor, such as aproximity sensor (capacitive or inductive), which senses the presence orabsence of the fill line connector received within the docking port. Theproximity sensor is therefore located near the identifier reader. Thesensor senses when the connector is removed from the docking unit, atwhich point it is assumed that the patient is about to connect theconnector to the transfer set to begin filling. The sensed removal ofthe connector is communicated to the transfer set to begin (or beginafter a short delay) the running of the fill duration. The running ofthe fill and dwell durations then proceeds according to the previousembodiment.

It is therefore an advantage of the present disclosure to provideperitoneal dialysis (“PD”) systems and methods that optimize therapydwell times for a patient.

It is another advantage of the present disclosure to provide peritonealdialysis (“PD”) systems and methods that streamline therapy time.

It is a further advantage of the present disclosure to provideperitoneal dialysis (“PD”) systems and methods that operate with CAPD aswell as APD.

It is still another advantage of the present disclosure to provideperitoneal dialysis (“PD”) systems and methods that operate withdifferent types and volumes of dialysate supplies or solutions.

It is still a further advantage of the present disclosure to provideperitoneal dialysis (“PD”) systems and methods that preclude the use ofan expired solution.

Additional features and advantages are described herein, and will beapparent from the following Detailed Description and the figures.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a prior art peritoneal dialysis system.

FIG. 2 is a control system for a peritoneal dialysis system according tothe present disclosure.

FIG. 3 is schematic view of a more detailed control system for aperitoneal dialysis system.

FIGS. 4A and 4B are two embodiments of remote connectors that may beused with the control system.

FIGS. 5 to 8 are graphs of peritoneal parameters and values ofperitoneal parameters as they relate to dwell times for the peritonealdialysis fluid.

FIG. 9 is a flow chart for a method of determining a dwell time for anoptimal therapy outcome.

FIG. 10 is a perspective view of an alternative embodiment of thepresent disclosure, which employs a smart transfer set.

FIG. 11 is a schematic view of one software and electrical layout forthe system and method of FIG. 10.

FIG. 12 is a flow chart for one method for implementing a dialysistreatment using a smart patient transfer set.

FIG. 13 is a flow chart for a second method (having two versions) forimplementing a dialysis treatment using a smart patient transfer set.

DETAILED DESCRIPTION Optimizing Therapy

Patients respond differently to peritoneal dialysis. There are a host ofvariables or parameters involved in peritoneal dialysis. One object ofthe present disclosure is to discuss these therapy variables orparameters and show how they can be used in tailoring the therapy, andto show how that therapy can be tailored for the best possible outcomefor that patient. Optimal execution of peritoneal dialysis therapy canhelp patients avoid numerous inefficiencies. These inefficienciesinclude the unnecessary loss of ultrafiltrate due to excessive dwelltimes, unnecessary carbohydrate absorption from long dwell times, andsuboptimal urea (“Kt/V”) and creatinine (“Ccr”) clearances.

Rather than using a standard 14-15 hour daytime automated peritonealdialysis (“APD”) regimen, or a standard 9-10 nighttime continuousambulatory peritoneal dialysis (“CAPD”) regimen, a dwell time iscalculated that is better suited to each patient. The dwell time dependson the patient's transmembrane transport capabilities, usually expressedas the patient's status as determined by a peritoneal equilibration test(“PET”). As an example of one benefit, carbohydrate (“CHO”) absorptiondoes not peak during peritoneal dialysis dwell times, but continues at asteady pace. The carbohydrate (e.g., glucose or icodextrin) inperitoneal dialysis solutions creates an osmotic gradient, enabling masstransport through the peritoneum. It is well known that this osmoticgradient decreases drastically during a long dwell time, most likelycaused by absorption of the CHO itself into the peritoneum. Accordingly,shorter dwell times will reduce CHO absorption and free the patient forother activities.

One basic difference among patients is the rate at which water andmetabolic wastes pass from the patient's bloodstream through theperitoneal membrane. Once the water and wastes pass through theperitoneal membrane, they are absorbed into the dialysis therapy fluidthat has been placed into the patient's peritoneal cavity, and thenremoved from the patient. A peritoneal equilibration test (PET)determines the relative rate of transmembrane transport. Patients canthen be classed as high-rate transporters, high-average transporters,low-average transporters, or low-rate transporters, depending on thespeed of waste removal. Other classification schemes may also be used,such as simply high, average, and low transporters. Patients may also beclassified in terms of their total body surface area (BSA), e.g., ahigh, average, or low BSA. The total body water volume may also be usedas an input parameter to help predict transport characteristics of thepatient.

In general, the rate of water removal is different from the rate ofwaste removal, and both depend on the patient transporter type. Forexample, fast transporters can quickly pass metabolic waste, but glucosefrom the dialysis solution is rapidly absorbed into the body. As aresult, glucose concentration in the dialysate decreases and the osmoticgradient diminishes within a relatively short period of time, dependingon the patient transporter type. For instance, high transporters maybenefit more from short dwell times, such as those used in automatedperitoneal dialysis (APD), where the effect of high osmotic gradients isstill present.

Conversely, the osmotic gradient will be sustained for a longer periodof time in the case of a low transporter patient, resulting in a largervolume of ultrafiltrate removal. Such a patient will likely benefit froma longer dwell time, such a continuous ambulatory peritoneal dialysis(CAPD) and with perhaps only a single nighttime exchange. Much usefulinformation about a patient's response to therapy can be learned fromadministering the PET test to the patient. The results of the PET testcan then be used to administer the therapy that would lead to the bestoutcome for that patient.

Another variable in peritoneal dialysis is the fill volume, that is, thevolume infused into the patient's peritoneum at the beginning of thedwell. The fill volume should be tailored to the comfort of the patientand the efficacy of the therapy. Fill volumes typically range from about1.5 liters to about 3 liters, i.e., from about 1500 ml to about 3000 ml.

Therapy outcomes differ based on the fill volume, and they also differbased on the particular therapy fluid or peritoneal dialysis fluid used.For example, peritoneal dialysis fluids, such as Dianeal® from BaxterInternational, Deerfield, Ill., U.S.A., may contain from 1.5% to 4.25%glucose. Other solutions may also be used. The glucose is used toprovide a large osmotic pressure gradient between the infused dialysatesolution and the patient's bloodstream, in order to draw excess waterfrom the patient, i.e., ultrafiltrate. Other fluids may have otherosmotic agents, such as icodextrin, e.g., 7.5% icodextrin in Extraneal®from Baxter International, which is typically used for longer dwelltimes.

The inputs to a particular dialysis therapy are thus seen to include atleast the patient characteristics, i.e., his or her unique response totherapy, the therapy solution used, the total volume of therapysolution, and the dwell time used for the therapy. As discussed above,the outputs of the therapy are the results of the therapy. These resultsinclude the amount of water removed, typically expressed as netultrafiltrate volume.

Other results or therapy outcomes include urea clearance, sometimesexpressed as Kt/V, creatinine clearance (Ccr), and total carbohydrateabsorption (CHO, also known as glucose or icodextrin absorption). Othertherapy outcomes may also be measured, such as sodium removal, phosphateclearance, and middle molecule clearances, e.g., β₂-microglobulin. Notethat an optimum therapy outcome requires high removal of urea andcreatinine, as well as other wastes and ultrafiltrate. However,carbohydrate absorption should be minimized. As noted above, water canbe transported both ways across the peritoneal membrane. Thus, netultrafiltrate should be positive, with water removed, rather than havingwater absorbed from the peritoneal dialysis fluid, which wouldconstitute negative ultrafiltration, and which is possible in a hightransporter with a long dwell time.

In order to optimize therapy outcomes for individual patients, kineticmodeling has been undertaken using the above variables. Kinetic modelingsoftware, PD Adequest 2.0™, is from Baxter International, Deerfield,Ill., U.S.A. This program uses a three-pore model of a patient'speritoneal membrane, and accepts choices of high, high-average,low-average, and low patient parameters, and uses a body surface area(BSA) input from 1.7 to 2.0 m². In developing the data presented herein,fill volume inputs of 1.5 L, 2 L, 2.5 L and 3 L were used, as weretherapy fluid inputs of 1.5%, 2.5% and 4.25% glucose Dianeal, andExtraneal with 7.5% icodextrin.

The results were tabulated in tables and plotted on graphs. An exampleof different dwell times and the modeled results is depicted in Table 1below.

TABLE 1 high transporter, 2 L fill, 2.5% Dianeal ® Creatinine GlucoseUrea Dwell time, Urea removal, absorption, clearance, hours UF, mlremoval, g L/wk/1.73 g. Kt/V 2.5 133 1.84 10.7 30.5 0.32 5 69 2.01 12.638.6 0.35 6 24 1.99 12.7 40.1 0.34 10 −184 1.81 11.87 42.6 0.31

Table 1 clearly shows that a shorter dwell time is better for ahigh-transporter patient. After 2.5 hours, the net ultrafiltrate (UF) ishighest, 133 ml net ultrafiltrate, with high levels of urea andcreatinine removal as shown. Allowing the therapy fluid to dwell forfive hours has a deleterious effect: the net ultrafiltrate has decreasedby about half, to abut 69 ml, and glucose absorption has increased byabout 25% to 38.6 g. Because the volume of ultrafiltrate continues todecrease, this patient may already have reached a point of diminishingreturns, at least for ultrafiltrate volume.

The only benefit from increased dwell time is a small increase in ureaand creatinine removal. However, if there were some medical reason to doso, one could select the urea removal or creatinine removal as theoutcome of interest, and select the appropriate dwell time, 5 hours forurea removal or 6 hours for creatinine removal. This selection wouldoptimize the value of the particular desired outcome, whether netultrafiltrate, urea removal, or creatinine removal, or the removal ofother solutes, such as phosphate or β₂-microglobulin that are notquantified here.

Another example for a high-transporter patient is depicted in Table 2below, in which the principal change is to use 2.5 L fill volume ratherthan 2 L.

TABLE 2 high transporter, 2.5 L fill, 2.5% Dianeal ® Creatinine GlucoseUrea Dwell time, Urea removal, absorption, clearance, hours UF, mlremoval, g L/wk/1.73 g. Kt/V 3 165 2.30 13.32 38.0 0.40 6 86 2.52 15.7848.4 0.44 7 40 2.50 15.91 50.0 0.43

Table 2 depicts results of using additional fill volume and slightlylonger dwell times. Using the additional 500 ml of fill volume hascaused an increase in net ultrafiltrate, to 165 ml, with increases inurea and creatinine removal over the amounts removed with 2.5 hoursdwell and a 2 L fill volume. While these are desirable, there has beenan increase in glucose absorption. The caregiver or medical professionalcan decide whether the increased ultrafiltration, urea removal andcreatinine removal is sufficient to justify an increase in glucoseabsorption. The desired outcome is then used to select the dwell timefor the patient, as well as whether it is desirable to use 2 L fillvolume or 2.5 L fill volume. Other examples are given below for othertransporter conditions.

TABLE 3 high-average transporter, 2 L fill, 2.5% Dianeal ® CreatinineGlucose Urea Dwell time, Urea removal, absorption, clearance, hours UF,ml removal, g L/wk/1.73 g. Kt/V 3.5 181 2.21 10.04 30.04 0.33 6 125 2.3511.87 36.93 0.35 8 40 2.30 12.26 39.82 0.34

TABLE 4 high-average transporter, 2.5 L fill, 2.5% Dianeal ® CreatinineGlucose Urea Dwell time, Urea removal, absorption, clearance, hours UF,ml removal, g L/wk/1.73 g. Kt/V 4 222 2.74 12.29 36.77 0.41 7 160 2.9414.82 46.00 0.44 10 29 2.86 15.41 50.41 0.43

Tables 3 and 4, for high-average transporters, demonstrate a shift ofpeak time points to longer dwell times. The ultrafiltration volumes arehigher at these longer dwell times, higher than the ultrafiltrationvolumes for the high-transporter Tables 1 and 2. There are also greaterurea and creatinine removals.

TABLE 5 low-average transporter, 2 L fill, 2.5% Dianeal ® CreatinineGlucose Urea Dwell time, Urea removal, absorption, clearance, hours UF,ml removal, g L/wk/1.73 g. Kt/V 4 209 2.45 9.14 26.80 0.32 7 173 2.6711.34 34.50 0.35 11 28 2.58 12.08 39.64 0.33

TABLE 6 low-average transporter, 2.5 L fill, 2.5% Dianeal ® CreatinineGlucose Urea Dwell time, Urea removal, absorption, clearance, hours UF,ml removal, g L/wk/1.73 g. Kt/V 5 258 3.10 11.69 34.37 0.40 9 193 3.3514.50 44.57 0.43 13 41 3.23 15.17 49.64 0.42

Tables 5 and 6 demonstrate shift of peak time points to even longerdwell times for low-average transporter patients. The ultrafiltrationvolumes are higher at these longer dwell times, higher than theultrafiltration volumes for the high-transporter Tables 1 and 2 and forhigh-average transporter Tables 3 and 4, especially with a 2.5 L fill.There are also greater urea and creatinine removals, urea removalpeaking at about 9 hours.

TABLE 7 low transporter, 2 L fill, 2.5% Dianeal ® Creatinine GlucoseUrea Dwell time, Urea removal, absorption, clearance, hours UF, mlremoval, g L/wk/1.73 g. Kt/V 6 335 2.24 9.01 26.94 0.37 9 287 2.33 10.6632.83 0.38 15 49 2.16 11.63 39.42 0.35

TABLE 8 low transporter, 2.5 L fill, 2.5% Dianeal ® Creatinine GlucoseUrea Dwell time, Urea removal, absorption, clearance, hours UF, mlremoval, g L/wk/1.73 g. Kt/V 7 409 2.79 11.14 33.42 0.46 11 342 2.9113.48 41.76 0.48 16 148 2.78 14.58 47.97 0.45

Tables 7 and 8 show that the low transporter patients benefit fromlonger dwell times, in clear contrast with the high transporterpatients. The ultrafiltration volumes are significantly increased, andmay already have peaked since the volumes are decreasing. Urea removalpeaks at 9 and 11 hours respectively

These data can be used to select a dwell time for the best possibleoutcome of a dialysis therapy session for a specific patient. Dialysistherapy is typically conducted with a peritoneal dialysis machine, suchas the machine depicted in FIG. 1. One suitable peritoneal dialysismachine is the HomeChoice® peritoneal dialysis machine from BaxterInternational, Deerfield, Ill., U.S.A. A patient P is connected to adialysis machine 1, shown within the dashed lines, with a patient accessdevice 5, such as an implanted catheter as shown. The catheter may be asingle lumen or double lumen catheter, or another type of access devicemay be used. A plurality of containers 2 of dialysis solution isconnected to the dialysis machine, as shown, through valves or otherconnectors. A pump 3 is used to transport dialysis fluid from thecontainers 2, one at a time, through a balance chamber 4 to theperitoneal cavity of the patient P through the access device. After theperitoneal dialysis solution has remained within the patient for thedesired dwell time, the same pump 3 or another pump 6 may be used topump the spent dialysis solution through the balance chamber 4 and thento a drain 7.

In embodiments discussed herein, a dialysis machine 1 may be used with adialysis control system 10 as depicted in FIG. 2. Dialysis controlsystem 10 includes an operating portion, such as the peritoneal dialysismachine depicted in FIG. 1, including fluid lines 12 for connection topatient access device 15. The operating section 11 performs dialysis forthe patient under the supervision of a control unit 13. Control unit 13in one embodiment has at least an input keypad 14, control panel 14 a,which may be a touch screen, input number pad 14 b, and mouse 14 c. Thecontrol unit will also include input drive 15 a, which may be suitablefor a floppy drive or for a CD drive. The computer in this embodiment isconfigured with a port for Internet access 15 b, as well as additionalinputs and outputs, including ports 16. The additional input ports maybe any combination of serial ports, such as USB ports, or parallelports.

In some embodiments, the control unit will be adapted to receivecommands from a remote control unit, and will include an IR receiver 15c for a hand-held remote. Inputs/outputs may include an optical input oroutput 15 d and other digital or analog inputs. Control portion 15 eincludes a series of controls knobs or switches for operating thedialysis machine. A speaker output 17 can alert the patient or acaregiver if there is an emergency or other malfunction of the dialysismachine. There is also a visual alarm 15 f for alerting the patient orcaregiver. The control section includes an antenna 19 for receivingremote commands or information. The antenna may be used forcommunication with a wireless device for the patient, as discussedbelow. The antenna may also be used for wireless (WiFi) internet accessor may be used for remote, but closer, commands.

FIG. 3 depicts a closer view of the control portions 30 of the dialysismachine 10. Machine control portion 30 is in communication with a“smart” patient control portion 40. As seen in FIG. 3, the communicationis wireless, for convenience and mobility of patients, such as mobileCAPD patients. However, those with skill in the art will recognize thata wire harness or cable could also connect the two portions. Dialysismachine control portion 30 includes a supervisory microcontroller 31,which receives power from a power supply 32. The microcontrollerreceives inputs from at least a keypad 33, and may also receive data andcommands from a wired connection 34, such as from a clinic or hospitalinformation system. Inputs may also be received from the patient viawireless connection and radio 35. The microcontroller has outputs to avideo monitor 36, a speaker 37, as well as controls to the dialysatepumps 38 and a heater 39 for the dialysate. The machine control systemincludes at least one memory as a part of the microcontroller 31 oraccessible by the microcontroller 31.

The patient control portion 40, as noted above, is not attached to thedialysis machine, enabling a mobile patient to move about without a wireharness or other connecting cable. Of course, other embodiments mayinclude a cable, infrared (IR) or RF communications instead of the radiodescribed herein. The patient control portion includes a separatemicrocontroller 42 and power supply 43, such as a battery 42. Thecontroller 42 receives input from the radio 41, with outputs through theradio and to an audio alarm or speaker 45 and a small video monitor 46.In some embodiments, the patient control portion may also includeswitches or other electromechanical inputs for signaling themicrocontroller 42 or for controlling the operation of the patientcontrol portion 40.

The signal processing circuitry and radio 41 or wirelessreceiver/transmitter are small and compact, and are easily placed on thepatient at the access site, such as in a “smart” module or connector.One radio that works is a wireless module in accord with ZigBee/IEEE805.15.4. This is a standard for a very low power radio system with avery limited range, about 10-20 feet. Modules made in accordance withthis standard may be purchased from Maxstream, Inc., Lindon, Utah,U.S.A., Helicomm, Inc., Carlsbad, Calif., U.S.A., and ANT, Cochrane,Alberta, Canada. The module is very small, and may be about 2 cm square(about 1 inch square), and about 3 mm thick (⅛ inch). The patientcontrol portion 40, as noted, is intended for close proximity, withinrange of the ZigBee module, of about 10-20 feet, of the dialysismachine. Thus, the local portion or signal module is conveniently smalland unobtrusive for the patient, but fully capable of communication andcontrol with the machine control portion 30.

The patient may use the patient control portion or may simply use thedialysis machine, such as the embodiment depicted in FIG. 2. In oneembodiment, shown in FIG. 4a , the patient P is connected to thedialysis machine through patient line 18, through patient control deviceand transfer set 50, and a catheter serving as a peritoneal accessdevice 47. Patient control device 50 is connected via luer connectors49, or other suitable connectors. The present day transfer set, intowhich the patient control device can be integrated, includes a length oftubing with a clamp, the length of tubing including one luer connector,such as a titanium luer, for connecting to the patient access device anda second luer for connecting to the patient line. Those who have skillin the art will recognize that patient transfer sets vary in regards tothe connectors used, and also vary in the clamp (not shown) or clampsused.

In this embodiment, the patient access device 47 is a double-lumencatheter and the patient line 18 includes two lengths of tubing. Patientcontrol device 50 includes an audio alarm or speaker 45 and a lamp 52,such as an LED, to alert a patient when the therapy session has begun orhas ended. Two lamps may be used, such as a green lamp when therapy hasbegun and a red lamp to alert the patient that the therapy session hasended. In one embodiment, patient control device 50 can be disengagedand separated from the tubing or transfer set for cleaning, replacement,and so forth. In another embodiment, the device cannot be disengaged andis embedded within the transfer set in such a manner as to extend thefunctions of the transfer set, without significantly impacting thevolume or area (footprint) of the transfer set.

Another embodiment 40 of the patient control device, and itsapplication, is depicted in FIG. 4B. Patient P is connected to thedialysis machine through a single-lumen patient line 18, patient controldevice and transfer set 40, and a single-lumen catheter 48 serving as apatient access device. Patient control device 40 is connected via luerconnectors 49 or other suitable connectors. The patient control device40 includes a small video output 46 and a lamp 52. An audio alarm 45 maybe used to signal the patient to begin or end a therapy session. Thevideo output 46 is suitable for displaying a time remaining on thedialysis session. Lamp 52 may be used to signal the patient, asdiscussed above. The patient control device 40 also includes twoswitches 51, suitable for allowing the patient to respond to queriesfrom the microcontroller 42. The switches, in this embodiment, are “yes”and “no” switches that are suitable for responding to queries from thecontroller, such as “shall we start the dialysis session?” or “pleaseenter a start time for the dialysis session.”

In addition to tabular data, as might be expected in a look-up table,the correspondence between dwell times and therapy outcomes can beexpressed as equations, and can be presented in graphical format, asshown in FIGS. 5-8. Each of these figures depicts performance for apatient according to the PET test status of the patient, as explainedabove for the tables. FIG. 5, for instance, for a high-transporterpatient (H), depicts therapy outcomes for patients that have beendialyzed with 2 L or 2.5 L of 2.5% glucose Dianeal® peritoneal dialysissolution. The solid lines depict 2.5 L results and the dotted linesdepict 2 L results, for net ultrafiltrate (read on the scale on the leftside of the graph), urea removed (read on the scale on the right side ofthe graph), and creatinine removal (also read on the scale on the rightside of the graph). The data demonstrate that net ultrafiltrate peaks atabout 2.5 or 3 hours for both a 2 L or a 2.5 L fill for ahigh-transporter patient. Urea removal peaks at about 4 hours with a 2 Lfill (dotted line), or at about 6 hours for a 2.5 L fill (solid line).For creatinine, clearance peaks at about 6 hours for a 2 L fill and atabout 7 hours for a 2.5 L fill.

Using this data, a patient or a caregiver, such as a medicalprofessional, can select a dwell time based on the desired outcome,e.g., 3 hours dwell time with a 2.5 L fill for maximum ultrafiltrate. Ifthe desire is to accommodate more than one desired outcome, a compromisecan be reached by interpolating between the desired outcomes. Forinstance, both high ultrafiltrate and high urea removal may be desired.For a 2.5 L fill, maximum urea removal occurs at about 6.5 hours. Adwell time between 3 and 6.5 hours may be selected, based on averagingthe two times, such as 3+6.5=9.5, and then dividing by two, to arrive atabout 4.75 hours. If one outcome or therapy result is deemed moreimportant, a weighted average may be used. For example, ifultrafiltration is more important, the time for the best ultrafiltrationoutcome may be multiplied by a weighting factor of 2, while using aweighting factor of 1 for the creatinine dwell time. In this case, theresult would be (3×2)+6.5=12.5, and then dividing the result by three,to arrive at a dwell time of about 4.2 hours. Weighting factors may bepre-selected and may be programmed into a computer program to calculatea resultant dwell time.

FIG. 6 depicts therapy outcomes for a patient whose PET status is thatof a high-average (HA) transporter. The kinetic modeling wasaccomplished using parameters of 2.5% glucose Dianeal®, with 2 L and 2.5L fill volumes. In these results, the creatinine has a very subtle peakremoval at about 9 hours, with very little effect from adding orsubtracting two hours from the dwell time. The ultrafiltration and urearemoval curves are shifted somewhat to the right, with greater dwelltimes, in comparison with those of FIG. 5 for H transporters. In otherwords, HA transporters act more slowly and need more time than Htransporters, which is to be expected.

FIG. 7 depicts results for low-average (LA) transporters, with the sameinput parameters of 2.5% glucose Dianeal®, with 2 L and 2.5 L fillvolumes. The curves for creatinine now have no peak, suggesting thatlonger dwell times result in additional cumulative creatinine transport.The curves for urea removal now have more subtle peaks, and the curvesfor both urea and ultrafiltrate are shifted toward even longer dwelltimes.

FIG. 8 demonstrates great differences in transport properties for low(L) transporter patients. In comparison with patients having highertransport status, low transporters have much higher rates ofultrafiltration and slower rates of waste removal. The ultrafiltrationcurves, the highest two curves on the left side of the chart, have muchhigher rates (note that the left-hand scale is changed from the previousgraphs). After about 6-7 hours, depending on the fill, theultrafiltration reverses, i.e., dialysis solution is being absorbed intothe patient's peritoneum, rather than ultrafiltrate being expressed intothe dialysis solution. The ultrafiltration curves are thus the lowesttwo curves at the longest dwell times (right side of chart). Creatinineremoval does not peak, even at 16 hours, while urea removal peaks atabout 9 hours (2 L fill) and about 10 hours (2.5 L fill).

Many additional data may also be used to understand the transportbehavior of peritoneal dialysis patients, as shown in the tables below,which concern respectively, performance at fill volumes of 1500 ml (1.5L), 2000 ml (2 L), 2500 ml (2.5 L), and 3000 ml (3 L). These data aredepicted respectively in Tables 9-12.

TABLE 9 1500 ml (1.5 L) volume fill 1.5% Dianeal Solution 2.5% Dianealsolution 4.25% Dianeal Solution Extraneal Solution Dwell Net UF Kt/VDwell Net UF Kt/V Dwell Net UF Kt/V Dwell Net UF Kt/V H 3.0 18 2.0 1033.0 294 16 534 3.5 .24 4.0 .26 5.0 .29 16 .35 HA 1.5 25 2.5 140 4.0 39416 594 4.0 .24 5.0 .28 6.0 .31 16 .35 LA 2.0 28 3.5 164 5.0 463 16 5485.0 .29 6.0 .26 7.0 .31 16 .34 L 2.5 5.6 5.0 260 7.0 693 16 665 6.0 .257.0 .29 9.0 .36 16 .37

TABLE 10 2000 ml (2 L) volume fill 1.5% Dianeal 2.5% Dianeal 4.25%Dianeal Extraneal Solution solution Solution Solution Net Net Net NetDwell UF Kt/V Dwell UF Kt/V Dwell UF Kt/V Dwell UF Kt/V H 1.5 24 2.5 1333.5 375 16 651 4.0 .32 5.0 .35 6.0 .38 16 .46 HA 2.0 34 3.5 181 5.0 50016 700 5.0 .32 8.0 .35 7.0 .41 16 .46 LA 2.5 37 4.0 209 7.0 586 16 6307.0 .31 7.0 .35 9.0 .41 16 .45 L 3.5 75 6.0 335 9.0 877 16 750 8.0 .339.0 .38 11.0 .48 16 .47

TABLE 11 2500 ml (2.5 L) volume fill 1.5% Dianeal 2.5% Dianeal 4.25%Dianeal Extraneal Solution solution Solution Solution Net Net Net NetDwell UF Kt/V Dwell UF Kt/V Dwell UF Kt/V Dwell UF Kt/V H 1.5 31 3.0 1654.0 457 16 739 5.0 .41 6.0 .44 7.0 .49 16 .56 HA 2.0 42 4.0 222 6.0 60616 777 6.0 .40 7.0 .44 8.0 .50 16 .59 LA 3.0 47 5.0 258 8.0 712 16 6898.0 .39 9.0 .43 11.0 .51 16 .53 L 4.0 93 7.0 408 10.0 1065 16 825 9.0.42 11.0 .48 13.0 .58 16 .57

TABLE 12 3000 ml (3 L) volume fill 1.5% Dianeal 2.5% Dianeal 4.25%Dianeal Extraneal Solution solution Solution Solution Net Net Net NetDwell UF Kt/V Dwell UF Kt/V Dwell UF Kt/V Dwell UF Kt/V H 2.0 38 3.5 1975.0 545 16 806 5.0 .49 7.0 .52 8.0 . .59 16 .65 HA 2.5 52 5.0 264 7.0719 16 836 7.0 .48 3.0 .52 10.0 .60 16 .65 LA 3.5 57 6.0 302 9.0 839 16730 9.0 .47 10.0 .52 12.0 .81 16 .61 L 5.0 112 8.0 465 12.0 1249 16 87210.0 .50 12.0 .57 15.0 .70 16 .66

The tables demonstrate that some of the trends discussed above hold trueacross many variables, e.g., ultrafiltration increases with decreasingtransport properties, and ultrafiltration also increases with increasingfill volume. Other trends can also be discerned, but the point remainsthe same: the data can be used to select a dwell time to optimize thedialysis session for a particular patient, based on the patient'stransport properties, fill volume, and dialysis solution used.

It is understood that the tables are simply an easy way to present data.The correspondence between dialysis input parameters, desired therapyoutcomes, and dwell times may reside as data in one or more tables, suchas look-up tables. The data may also take the form of graphs, or may bereduced to equations. There are many embodiments of the invention,including all of these methods of presenting, storing, and using thedata.

A flowchart for a method of optimizing a therapy session is depicted inFIG. 9. The classification of the patient as a high transporter,high-average transporter, and so forth, is determined by administering91 a PET test. In other embodiments, other tests may be used, and otherclassifications may be used. The point is to determine how eachindividual patient can benefit from the dialysis conditions best suitedfor him or her. In any event, the transport properties of the patientwith respect to ultrafiltration and waste transport are determined 92.The patient or a caregiver, such as a medical professional, determines93, e.g., selects, at least one desired outcome of a dialysis treatment,such as ultrafiltrate volume or urea clearance.

A dwell time for optimizing the selected outcome is then calculated orestimated 94. The selected dwell time is then entered 95 into thecontroller of the dialysis machine. For dialysis treatments that do notnecessarily involve a peritoneal dialysis machine, such as ambulatoryperitoneal dialysis, the controller may simply be a timer on thetransfer set. The therapy session is then conducted 96 using the entereddwell time. At the end of the dwell time, the timer or other alertingdevice alerts 97 the patient that the dwell time has expired and thetherapy session may be ended.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the present subjectmatter and without diminishing its intended advantages. It is thereforeintended that such changes and modifications be covered by the appendedclaims.

Smart Patient Transfer Set

In a further embodiment, the present disclosure sets forth a peritonealdialysis “smart” system and method for performing peritoneal dialysis,which is applicable to both continuous ambulatory peritoneal dialysis(“CAPD”) and automated peritoneal dialysis (“APD”) therapies. The systemand method take advantage of one common component for both CAPD and APD,namely, that both types of systems include or connect to a patient'stransfer set. As discussed above, the patient's transfer set is apermanent item worn and carried around by the patient. The set isconnected to a tube that transitions to an indwelling catheter locatedwithin the patient's peritoneal cavity.

The patient's transfer set connects to a connector located at the end ofa patient fill tube. The fill tube can extend from a manual flow controldevice for CAPD or a disposable cassette for APD. The manual flowcontrol device connects to a single supply bag typically. The disposablecassette connects to multiple supply bags typically. Thus anotherconstant with CAPD and APD systems is the use of at least one supplybag.

The system places a readable identifier on a connector located at theend of a tube or pigtail extending from the supply bag. Alternatively,the identifier is placed on the tube or pigtail itself. Furtheralternatively, if the bags do not include tubes or pigtails and areinstead spiked, the bags themselves may be provided with identifiersthat are read. Still further alternatively, in an APD embodiment theidentifier can be placed on a connector connected to a patient fill linerunning from the APD machine. The identifiers in any case can be abarcode or radio frequency identifier, for example.

A reader is provided that reads the identifier. The reader can beintegrated into the APD machine or be provided in a standalone unit. Itis contemplated to use the standalone unit in both APD and CAPDtherapies. The reader reads the identifier, processes the informationobtained from the identifier, and sends a signal based on the processedinformation.

The patient's transfer set receives the signal sent from the reader. Thesignal may be a wireless signal sent from a transmitter (or transceiver)of the reader to a receiver (or transceiver) of the transfer set. Thetransceivers are provided alternatively for two-way communicationbetween the reader and the transfer set. The transfer set is alsoprovided with microprocessing and memory that are programmed to act onthe received information. The microprocessor outputs to an outputdevice, such as an alarm and/or readout, that communicates informationto the patient. In one example, the supply container identifier suppliesinformation regarding the volume of fluid in the supply container and adextrose or glucose level of the dialysate residing in the container.The identifier may also include expiration date information for thesupply.

Referring now to FIGS. 10 and 11, one embodiment of a smart transfer setsystem 130 and corresponding method is illustrated. System 130 includestwo primary components, namely, an alternative control portion 140,which is hereafter called a remote docking unit, and an alternative orsmart transfer set 150. Remote docking unit 140 can be configured foroperation with control portion 30 of the dialysis machine 10 discussedabove for APD. Alternatively, docking unit 140 operates solely withsmart transfer set 150 to run a CAPD therapy.

Docking unit 140 accepts a supply line connector 118 having a tag oridentifier 120, which can be a barcode or radio frequency identification(“RFID”) tag. Tag or identifier 120 is placed alternatively on thesupply line itself, e.g., near supply line connector 118. Furtheralternatively, in APD application, supply line connector 118 can insteadbe a connector for the patient line 18 coming from APD machine 30.

Docking unit 140 includes a reader 147 positioned in suitable proximityto tag or identifier 120 to read the information from the tag. Reader147 can for example be a barcode scanner that faces barcode 120 to readits information. Reader 147 is alternatively an RFID reader that may nothave to be placed as directly adjacent to RFID tag 120 to read theinformation.

The information in one embodiment includes (i) the volume, (ii) the typeand (iii) the expiration date of solution or dialysis fluid held by thesupply bag connected to the supply line connected to supply lineconnector 118. If the dialysis fluid has expired, an alarm will beposted and if used with APD machine 10, system 130 will not allowtherapy to continue. The volume and type of dialysis solution is used toset fill and dwell times as discussed in detail below.

Docking unit 140 also includes a memory card or drive port 144, such asa universal serial bus (“USB”) port for receiving a memory storagemember 149, such as a flash drive or disk drive. The memory storagemember 149 stores patient specific data, such as data shown above inTables 1 to 12, which is combined with data from tag or identifier 120to determine an optimal dwell time for the patient. In one embodiment,memory storage member 149 needs to be inserted into port 144 for eachtreatment. In another embodiment, memory storage member 149 needs to beinserted only once into port 144 until the data on the memory storagemember 149 is changed.

In one alternative embodiment discussed below in connection with FIG.13, a separate proximity sensor 148 is provided. Proximity sensor 148can be a capacitive or inductive proximity sensor. The proximity sensorsenses the presence or absence of connector 118 for reasons discussedbelow.

Each of the reader 147, memory member receiving port 144 and proximitysensor 148 is linked to a controller 42 provided within docking unit140. In the illustrated embodiment (and for any of the embodimentsdiscussed herein), controller 42 includes processing 42 a and memory 42b. Processing 42 a and memory 42 b are also linked in communication witha wireless transmitter (Tx) or transceiver (Tc) 41, which communicateswirelessly with a receiver (Rx) or transceiver (Tc) 141 located withinsmart transfer set 150.

Controller 42 also commands one or more output device 45, such as alight and/or buzzer, which can for example communicate to the patientwhenever docking unit 140 is processing or transmitting data. Forexample, an alarm output device 45 can be provided to indicate when thatthe solution of a bag connected to connector 118 has expired. Outputdevice 45 can alternatively be a display which indicates “expired” inthis instance.

A power supply 43, which can be AC sourced, be a rechargeable battery orbe a replaceable battery supplies the appropriate power to each ofcontroller 42, output device 45, reader 147, transmitter (Tx) ortransceiver (Tc) 41 and proximity switch 148 (if provided). Low powercan be indicated to the patient via light indication or via a readout.

Processing 42 and memory 42 b receive the solution data from reader 147and patient data from memory storage member 149 and process the data toarrive at an optimal dwell time according to the methods describedherein. That optimal dwell time is then sent via transmitter (Tx) ortransceiver (Tc) 41 wirelessly (possibly with other information asdiscussed below) to receiver (Rx) or transceiver (Tc) 141 located withinsmart transfer set 150. Alternatively, docking unit 140 serves mainly asan information transfer device, which transfers solution data fromreader 147 and patient data from memory storage member 149 to smarttransfer set 150, which then uses its processing 142 a and memory 142 bto compute the optimal dwell duration (and other needed information asdiscussed below). It may be possible under one of these scenarios toremove or limit the processing and memory from one of docking unit 140and smart transfer set 150.

As seen in FIG. 11, smart transfer set 150 includes a controller 142having processing 142 a and memory 142 b, which accept information fromreceiver (Rx) or transceiver (Tc) 141 and command operation of one ormore patient output device, such as a light and/or buzzer 145 and asmall (e.g., liquid crystal display (“LCD”)) readout 146. In oneembodiment, discussed below in connection with FIG. 12, smart transferset 150 is provided with a patient input device 152, such as apushbutton or switch. Input device 152 inputs a signal to controller142, for example, to indicate when a fill of the solution from the bagto the patient has been completed.

Transfer set 150 also includes a power supply 143, which can be arechargeable battery or a replaceable battery, and which supplies theappropriate power to each of controller 142, receiver (Rx) ortransceiver (Tc) 141 and output devices 145 and 146. Again, low powercan be indicated to the patient via light indication or via a readout.

Referring now to FIG. 12, a method 160 for operating system 130 isillustrated. Upon beginning method 160 as seen at oval 162, dwellduration is determined as seen at block 164. Dwell duration iscalculated using the solution data from reader 147 and patient data frommemory storage member 149 and the methodology set forth herein by eitherthe controller 42 of docking unit 140 or controller 142 of smarttransfer set 150 as discussed above. Dwell time duration is thus eitherdetermined at smart transfer set 150 or sent to smart transfer set 150from docking unit 140, and in any case is known by smart transfer set150 at block 164.

At diamond 166, method 160 waits for the patient to press input device152 indicating that a fill from a supply bag connected to connector 118has been completed. Method 160 allows for the patient to fill as fast orslow as the patient desires and is independent of fill time. When thepatient presses input device 152 indicating that the fill is complete,method 160 proceeds to block 168, at which time the optimal dwellduration beings to run. Small display 146 at FIG. 11 shows oneembodiment in which dwell duration is counted backwards from thestarting duration down to zero. It is contemplated to build false inputdevice 152 activation protection into method 160, e.g., requiring aconfirm press of the input device or allowing a second press of theinput device to undue the original input and start over.

At diamond 170, method 160 waits for the dwell duration to run outcompletely, at which time the patient is alerted that dwell is finishedand that the patient should begin to drain the spent dialysate, as seenat block 172. Different scenarios are contemplated. For example,light/buzzer 145 could flash with five or ten minutes before dwell iscompleted to give the patient a heads-up the he/she needs to get to aplace appropriate for draining. All the while clock 146 is counting downto zero. At zero, light/buzzer 145 lights/sounds to indicate that dwellis complete and that drain needs to start as soon as possible. Thebuzzer can be for a predetermined duration, and input device 152 can beset to stop the buzzer immediately when pressed in case the patient doesnot want noise.

At oval 174, method 160 ends. Method 160 is then repeated for eachsupply bag of the therapy.

Referring now to FIG. 13, another method 180 (actually two versions ofthis methods as discussed below) for operating system 130 isillustrated. Upon beginning method 180 as seen at oval 182, fill anddwell durations are determined as seen at block 184. Dwell duration isagain calculated using the solution data from reader 147 and patientdata from memory storage member 149 and the methodology set forth hereinby either the controller 42 of docking unit 140 or controller 142 ofsmart transfer set 150 as discussed above. Dwell duration is in any caseis known by smart transfer set 150 at block 184. Both fill and dwelldurations are affected by the volume of the dialysis solution in thesupply container. Dwell duration is also affected by the type ordextrose level of the dialysis solution. Fill duration is also effectedby the patient's fill position relative to the supply container if thefill is a gravity fill. Position can play a role even when fluid ispumped from the supply bag to the patient. Thus, the fill duration maybe for a particular head height level, which is either known generallyby the patient or communicated via system 130 to the patient via the APDmachine 10, docking unit 140 or smart transfer set 150.

At block 186 a, the patient is alerted that the patient should beginfilling fresh dialysate from the supply container, through connector 118and transfer set 150, to the patient's peritoneum. Different scenariosare contemplated for the fill duration run-out indicated at block 188.For example, light/buzzer 145 could flash and or buzz, while display 146counts the fill duration down to zero. Display 146 could also displaythe word “fill” to indicate that the current countdown is for filling.Alternatively or additionally, light 145 could be lighted a differentcolor for fill (e.g., green) and dwell (e.g., yellow).

At diamond 190, method 180 waits for the fill duration to run outcompletely, at which time the patient is alerted that fill is supposedto be finished and that the dwell duration is beginning. Differentscenarios are contemplated dwell duration run-out indicated at block192. For example, light/buzzer 145 could flash and or buzz for a periodto indicate the transition from fill to drain, while display 146 resetsitself and counts now the dwell duration down to zero. Display 146 couldalso display the word “dwell” to indicate that the current countdown isfor filling. Alternatively or additionally, light 145 could be changedfrom, e.g., green to yellow. Method 180 accordingly does not requireinput device 152 because the method transitions automatically from fillto dwell.

At diamond 190, method 180 waits for the dwell duration to run outcompletely, at which time the patient is alerted that dwell is finishedand that the patient should begin to drain the spent dialysate, as seenat block 198. As with method 160, impending dwell completion can beindicated by the flashing of light/buzzer 145 with five or ten minutesbefore dwell is done to give the patient a heads-up the he/she needs toget to a place appropriate for draining. All the while clock 146 iscounting down to zero. At zero, light/buzzer 145 lights/sounds toindicate that dwell is complete and that drain needs to start as soon aspossible. The buzzer can be again be for a predetermined duration, andinput device 152 can be set to stop the buzzer immediately when pressedin case the patient does not want noise.

Block 186 b illustrates a modification of method 180. If there is goingto be a substantial error in estimating fill duration, it is likelygoing to involve an instance in which system 130 assumes the patient isdiligently following the time run-outs to meet the deadlines or timeexpirations. It may occur however that the patient becomes distracted orforgets that the fill time is underway. In either case, it is likelythat the patient will have left connector 118 positioned in its holdingport of docking unit 140. The modification via block 186 b assumes thatonce the patient has undertaken to remove connector 118 from dockingunit 140, that the patient will thereafter diligently connect connector118 to the transfer set for filling. Here, proximity sensor 148 senses aremoval of connector 118 from the docking unit, sends a signal tocontroller 42, which commands Tx/Tc 41 to send a corresponding wirelesssignal to Rx/Tc 141 of transfer set 150, which is routed to controller142, which then initiates the fill duration run-out sequence indicatedat block 188. If space permits, proximity sensor 148 can be locatedalternatively in transfer set 150, which then looks for the presence ofconnector 118 to begin the fill duration run-out. In either case, method180 is immune to patient delay in removing connector 118 from dockingunit 140.

It should be understood that various changes and modifications to thepresently preferred embodiments described herein will be apparent tothose skilled in the art. Such changes and modifications can be madewithout departing from the spirit and scope of the present subjectmatter and without diminishing its intended advantages. It is thereforeintended that such changes and modifications be covered by the appendedclaims.

The invention is claimed as follows:
 1. A method for accomplishingautomated peritoneal dialysis, comprising: administering a peritonealequilibration test (“PET”) to a patient; determining and recording apatient status as a result of the PET test, the patient status selectedfrom the group consisting of a high transporter, average transporter,low transporter, and combinations thereof; calculating a peritonealdialysis dwell time based on the patient status and at least oneperitoneal dialysis therapy outcome, wherein the dwell time optimizesthe at least one peritoneal dialysis therapy outcome for the patient,said calculating including (i) averaging an optimized dwell time for aplurality of peritoneal dialysis therapy outcomes or (ii) using aweighted average of an optimized dwell time of each of the plurality ofperitoneal dialysis therapy outcomes; and performing at least onetreatment cycle with the calculated peritoneal dialysis dwell time usingan automated peritoneal dialysis machine.
 2. The method of claim 1,wherein the step of calculating is based on a plurality of peritonealdialysis input parameters.
 3. The method of claim 1, further comprisingstoring a database of peritoneal dialysis dwell times, peritonealdialysis input parameter values and peritoneal dialysis therapy outcomesin a memory of a computer or in a memory accessible to the computer forcarrying out the step of calculating.
 4. The method of claim 1, whereinthe at least one peritoneal dialysis therapy outcome is selected fromthe group consisting of: a net ultrafiltrate volume, a net ultrafiltratevolume rate, an absorption of carbohydrates from a peritoneal dialysisfluid, a phosphate removal, a creatinine clearance, and a ureaclearance.
 5. The method of claim 1, wherein the step of calculating isalso based on a composition of a peritoneal dialysis fluid and aperitoneum fill volume.
 6. The method of claim 1, further comprisinginfusing a peritoneal dialysis fluid into a peritoneum of the patient;and notifying the patient when the dwell time has elapsed.
 7. A methodfor accomplishing automated peritoneal dialysis, comprising: determiningperitoneal transport properties of a patient; determining aclassification of the peritoneal transport properties of the patient;calculating a peritoneal dialysis dwell time based on theclassification, a plurality of peritoneal dialysis input parameters, andat least one desired peritoneal dialysis therapy outcome, wherein thedwell time is calculated to maximize the at least one desired peritonealdialysis therapy outcome, said calculating including (i) averaging anoptimized dwell time for a plurality of peritoneal dialysis therapyoutcomes or (ii) using a weighted average of an optimized dwell time ofeach of the plurality of peritoneal dialysis therapy outcomes; andperforming at least one treatment cycle with the calculated peritonealdialysis dwell time using an automated peritoneal dialysis machine. 8.The method of claim 7, further comprising storing data of acorrespondence between the plurality of peritoneal dialysis inputparameters, a plurality of therapy outcomes, and values of a peritonealdialysis dwell time in a memory of a computer or in a memory accessibleto the computer for carrying out the step of calculating.
 9. The methodof claim 7, wherein the at least one desired peritoneal dialysis outcomeis selected from the group consisting of: a net ultrafiltrate volume, anet ultrafiltrate volume rate, a reduction in absorption ofcarbohydrates from a peritoneal dialysis fluid, a urea clearance, asodium clearance, a middle molecule clearance, and a creatinineclearance.
 10. The method of claim 7, wherein the step of calculating isbased on a body surface area or a total body water volume of a patient.11. The method of claim 7, further comprising infusing a peritonealdialysis fluid into a peritoneum of the patient; notifying the patientwhen the dwell time has elapsed; and removing the peritoneal dialysisfluid from the peritoneum after the dwell time.
 12. A system forcalculating a peritoneal dialysis dwell time and conducting automatedperitoneal dialysis, the system comprising: a processor for operating anautomated peritoneal dialysis machine; a memory of the processor or amemory accessible to the processor, the memory storing a look-up tablecontaining peritoneal dialysis input parameters, peritoneal dialysistherapy outcomes, and peritoneal dialysis dwell times corresponding tothe input parameters and dwell times; and a software program stored inthe memory of the processor or the memory accessible to the processorfor receiving a selection or an input of at least one desired therapyoutcome of a patient and calculating a dwell time for the patient foroptimizing the at least one peritoneal dialysis therapy outcome for thepatient, wherein the dwell time is calculated by (i) averaging anoptimized dwell time for a plurality of peritoneal dialysis therapyoutcomes or (ii) using a weighted average of an optimized dwell time ofeach of the plurality of peritoneal dialysis therapy outcomes.
 13. Thesystem of claim 12, wherein the plurality of peritoneal dialysis therapyoutcomes include at least two of a net ultrafiltrate volume, anabsorption of carbohydrates, a urea clearance, a phosphate clearance,and a creatinine clearance.
 14. The system of claim 12, wherein thelook-up table includes input parameters based on transport properties ofthe patient, a composition of a peritoneal dialysis fluid, and aperitoneum fill volume, and optionally, a body surface area of thepatient or a total body volume of the patient.
 15. The system of claim12, further comprising a housing for the computer system and an inputdevice for inputting at least one peritoneal dialysis input parameter, acomposition of a peritoneal dialysis fluid, and inputting or selectingthe at least one dialysis therapy outcome.
 16. The system of claim 12,further comprising a remote device in communication with the computersystem, the remote device including an output device for indicating anend of the dwell time or a time remaining of the dwell time.
 17. Thesystem of claim 12, further comprising a patient transfer set, includingan output device for indicating an end of the dwell time or a timeremaining of the dwell time.
 18. The system of claim 12, furthercomprising a peritoneal dialysis machine, wherein the processor formspart of a control system of the peritoneal dialysis machine.
 19. Acomputer program embodied on a computer readable medium for calculatinga peritoneal dialysis dwell time, comprising: a code segment foraccessing data of a correspondence between a plurality of peritonealdialysis input parameters, a plurality of peritoneal dialysis therapyoutcomes, and a plurality of peritoneal dialysis dwell times; a codesegment that allows a user to input or to select at least one peritonealdialysis input parameter from the plurality of peritoneal dialysis inputparameters and at least one desired therapy outcome; a code segment thatreceives an indication of the at least one input parameter and at leastone desired therapy outcome selected by the user; a code segment thatcalculates a dwell time corresponding to the at least one desiredtherapy outcome selected by the user, said code configured to calculatethe dwell time by (i) averaging an optimized dwell time for a pluralityof peritoneal dialysis therapy outcomes or (ii) using a weighted averageof an optimized dwell time of each of the plurality of peritonealdialysis therapy outcomes; and a code segment that inputs the dwell timeto an automated peritoneal dialysis machine.
 20. The computer programaccording to claim 19 wherein the at least one desired therapy outcomeis selected from the group consisting of: a net ultrafiltrate volume, anet ultrafiltrate volume rate, an absorption of carbohydrates from aperitoneal dialysis fluid, a urea clearance, and a creatinine clearance.21. The computer program according to claim 19, further comprising thedata, said data stored on the computer-readable medium or in a memoryaccessible by the computer readable medium as a look-up table or as oneor more formulae that express the correspondence.
 22. An automatedperitoneal dialysis system, comprising: a dialysis cassette and ahousing suitable for receiving the cassette, the cassette including atleast one pump for pumping dialysis fluid to and from a patient; amicrocontroller suitable for operating the automated peritoneal dialysissystem; a memory of the microcontroller or accessible to themicrocontroller, the memory including data of a plurality of dialysisinput parameters, a plurality of dialysis dwell times, and a pluralityof therapy outcomes corresponding to the input parameters and dwelltimes, wherein a user instructs the microcontroller to select orcalculate a dwell time for optimizing at least one dialysis outcome fora patient; and a patient transfer device connected to a patient accessdevice, the patient transfer device including electronics incommunication with the microcontroller.